回归高低潮

ARI SHAPIRO, HOST: For decades, the Colorado River has fed growing cities from Denver to Los Angeles, and a lot of the produce in grocery stores across the country right now was grown with Colorado River water. Now with climate change and severe drou

发表于:2018-12-17 / 阅读(44) / 评论(0) 分类 2017年NPR美国国家公共电台1月

By Cathy Majtenyi Nairobi 19 May 2008 Fuel efficient stoves and ceramic water purifiers are two examples of low-tech innovations that can help people in poor countries improve their quality of life. Because what is known as appropriate technology usu

发表于:2019-01-10 / 阅读(62) / 评论(0) 分类 VOA标准英语2008年(五月)

Corn prices are surging on the world market after devastating floods in the U.S. heartland destroyed many crops shortly after they were planted. Corn is also in high demand these days, because it is used for making the alcohol fuel additive called e

发表于:2019-01-13 / 阅读(53) / 评论(0) 分类 VOA标准英语2008年(六月)

AILSA CHANG, HOST: Scientists announced today that they have figured out the cause of an outbreak of Legionnaires' disease in Flint, Mich., a few years ago. Twelve people died. This was at the start of the city's water crisis. And the problem was a l

发表于:2019-01-16 / 阅读(63) / 评论(0) 分类 2018年NPR美国国家公共电台2月

The living is easy. But it won't last long. At this altitude, the air is so dry that rain evaporates before it even hits the ground. The water that flows off the plateau is no longer being replaced. Already there is drought in forests beyond the mead

发表于:2019-01-22 / 阅读(44) / 评论(0) 分类 自然百科2012年

As the thaw reaches up into the mountains, a part of Yellowstone that few ever see is briefly revealed. From its first day above the snow, this pika is obsessed by food. It's in a frantic race to restock its winter larder before the snow closes in ag

发表于:2019-01-22 / 阅读(37) / 评论(0) 分类 自然百科2012年
学英语单词